function out = uipickfiles(varargin)
%uipickfiles: GUI program to select file(s) and/or directories.
%
% Syntax:
%   files = uipickfiles('PropertyName',PropertyValue,...)
%
% The current directory can be changed by operating in the file navigator:
% double-clicking on a directory in the list to move further down the tree,
% using the popup menu to move up the tree, typing a path in the box to
% move to any directory or right-clicking on the path box to revisit a
% previously-listed directory.
%
% Files can be added to the list by double-clicking or selecting files
% (non-contiguous selections are possible with the control key) and
% pressing the Add button.  Files in the list can be removed or re-ordered.
% When finished, a press of the Done button will return the full paths to
% the selected files in a cell array, structure array or character array.
% If the Cancel button is pressed then zero is returned.
%
% The following optional property/value pairs can be specified as arguments
% to control the indicated behavior:
%
%   Property    Value
%   ----------  ----------------------------------------------------------
%   FilterSpec  String to specify starting directory and/or file filter.
%               Ex:  'C:\bin' will start up in that directory.  '*.txt'
%               will list only files ending in '.txt'.  'c:\bin\*.txt' will
%               do both.  Default is to start up in the current directory
%               and list all files.  Can be changed with the GUI.
%
%   REFilter    String containing a regular expression used to filter the
%               file list.  Ex: '\.m$|\.mat$' will list files ending in
%               '.m' and '.mat'.  Default is empty string.  Can be used
%               with FilterSpec and both filters are applied.  Can be
%               changed with the GUI.
%
%   Prompt      String containing a prompt appearing in the title bar of
%               the figure.  Default is 'Select files'.
%
%   NumFiles    Scalar or vector specifying number of files that must be
%               selected. A scalar specifies an exact value; a two-element
%               vector can be used to specify a range, [min max].  The
%               function will not return unless the specified number of
%               files have been chosen.  Default is [] which accepts any
%               number of files.
%
%   Output      String specifying the data type of the output: 'cell',
%               'struct' or 'char'.  Specifying 'cell' produces a cell
%               array of strings, the strings containing the full paths of
%               the chosen files.  'Struct' returns a structure array like
%               the result of the dir function except that the 'name' field
%               contains a full path instead of just the file name.  'Char'
%               returns a character array of the full paths.  This is most
%               useful when you have just one file and want it in a string
%               instead of a cell array containing just one string.  The
%               default is 'cell'.
%
% All properties and values are case-insensitive and need only be
% unambiguous.  For example,
%
%   files = uipickfiles('num',1,'out','ch')
%
% is valid usage.

% Version: 1.0, 25 April 2006
% Author:  Douglas M. Schwarz
% Email:   dmschwarz=ieee*org, dmschwarz=urgrad*rochester*edu
% Real_email = regexprep(Email,{'=','*'},{'@','.'})


% Define properties and set default values.
prop.filterspec = '*';
prop.prompt = 'Select files';
prop.numfiles = [];
prop.output = 'cell';

% Process inputs and set prop fields.
properties = fieldnames(prop);
arg_index = 1;
while arg_index <= nargin
    arg = varargin{arg_index};
    if ischar(arg)
        prop_index = find(strncmpi(arg,properties,length(arg)));
        if length(prop_index) == 1
            prop.(properties{prop_index}) = varargin{arg_index + 1};
        else
            error('Property ''%s'' does not exist or is ambiguous.',arg)
        end
        arg_index = arg_index + 2;
    elseif isstruct(arg)
        arg_fn = fieldnames(arg);
        for i = 1:length(arg_fn)
            prop_index = find(strncmpi(arg_fn{i},properties,...
                length(arg_fn{i})));
            if length(prop_index) == 1
                prop.(properties{prop_index}) = arg.(arg_fn{i});
            else
                error('Property ''%s'' does not exist or is ambiguous.',...
                    arg_fn{i})
            end
        end
        arg_index = arg_index + 1;
    else
        error(['Properties must be specified by property/value pairs',...
            ' or structures.'])
    end
end

% Validate FilterSpec property.
if isempty(prop.filterspec)
    prop.filterspec = '*';
end
if ~ischar(prop.filterspec)
    error('FilterSpec property must contain a string.')
end

% Validate Prompt property.
if ~ischar(prop.prompt)
    error('Prompt property must contain a string.')
end

% Validate NumFiles property.
if numel(prop.numfiles) > 2 || any(prop.numfiles < 0)
    error('NumFiles must be empty, a scalar or two-element vector.')
end
prop.numfiles = unique(prop.numfiles);
if isequal(prop.numfiles,1)
    numstr = 'Select exactly 1 file.';
elseif length(prop.numfiles) == 1
    numstr = sprintf('Select exactly %d files.',prop.numfiles);
else
    numstr = sprintf('Select %d to %d files.',prop.numfiles);
end

% Validate Output property.
legal_outputs = {'cell','struct','char'};
out_idx = find(strncmpi(prop.output,legal_outputs,length(prop.output)));
if length(out_idx) == 1
    prop.output = legal_outputs{out_idx};
else
    error(['Value of ''Output'' property, ''%s'', is illegal or '...
        'ambiguous.'],prop.output)
end


% Initialize file lists.
[current_dir,f,e] = fileparts(prop.filterspec);
filter = [f,e];
if isempty(current_dir)
    current_dir = pwd;
end
if isempty(filter)
    filter = '*';
end
%re_filter = prop.refilter;
full_filter = fullfile(current_dir,filter);
path_cell = path2cell(current_dir);
fdir = filtered_dir(full_filter);
filenames = {fdir.name}';
filenames = annotate_file_names(filenames,fdir);

% Initialize some data.
file_picks = {};
full_file_picks = {};
dir_picks = dir(' ');  % Create empty directory structure.
show_full_path = false;
nodupes = true;
history = {current_dir};

% Create figure.
gray = get(0,'DefaultUIControlBackgroundColor');
fig = figure('Position',[0 0 740 445],...
    'Color',gray,...
    'WindowStyle','modal',...
    'Resize','off',...
    'NumberTitle','off',...
    'Name',prop.prompt,...
    'IntegerHandle','off',...
    'CloseRequestFcn',@cancel,...
    'CreateFcn',{@movegui,'center'});

% Create uicontrols.
uicontrol('Style','frame',...
    'Position',[255 260 110 70])
uicontrol('Style','frame',...
    'Position',[275 135 110 100])

navlist = uicontrol('Style','listbox',...
    'Position',[10 10 250 320],...
    'String',filenames,...
    'Value',[],...
    'BackgroundColor','w',...
    'Callback',@clicknav,...
    'Max',2);
pickslist = uicontrol('Style','listbox',...
    'Position',[380 10 350 320],...
    'String',{},...
    'BackgroundColor','w',...
    'Callback',@clickpicks,...
    'Max',2);

openbut = uicontrol('Style','pushbutton',...
    'Position',[270 300 80 20],...
    'String','Open',...
    'Enable','off',...
    'Callback',@open);
arrow = [2 2 2 2 2 2 2 2 1 2 2 2;...
    2 2 2 2 2 2 2 2 2 0 2 2;...
    2 2 2 2 2 2 2 2 2 2 0 2;...
    0 0 0 0 0 0 0 0 0 0 0 0;...
    2 2 2 2 2 2 2 2 2 2 0 2;...
    2 2 2 2 2 2 2 2 2 0 2 2;...
    2 2 2 2 2 2 2 2 1 2 2 2];
arrow(arrow == 2) = NaN;
arrow_im = NaN*ones(16,76);
arrow_im(6:12,45:56) = arrow/2;
im = repmat(arrow_im,[1 1 3]);
addbut = uicontrol('Style','pushbutton',...
    'Position',[270 270 80 20],...
    'String','Add    ',...
    'Enable','off',...
    'CData',im,...
    'Callback',@add);

removebut = uicontrol('Style','pushbutton',...
    'Position',[290 205 80 20],...
    'String','Remove',...
    'Enable','off',...
    'Callback',@remove);
moveupbut = uicontrol('Style','pushbutton',...
    'Position',[290 175 80 20],...
    'String','Move Up',...
    'Enable','off',...
    'Callback',@moveup);
movedownbut = uicontrol('Style','pushbutton',...
    'Position',[290 145 80 20],...
    'String','Move Down',...
    'Enable','off',...
    'Callback',@movedown);

uicontrol('Position',[10 380 250 16],...
    'Style','text',...
    'String','Current Directory',...
    'HorizontalAlignment','center')
dir_popup = uicontrol('Style','popupmenu',...
    'Position',[10 335 250 20],...
    'BackgroundColor','w',...
    'String',path_cell(end:-1:1),...
    'Value',1,...
    'Callback',@dirpopup);
hist_cm = uicontextmenu;
pathbox = uicontrol('Position',[10 360 250 20],...
    'Style','edit',...
    'BackgroundColor','w',...
    'String',current_dir,...
    'HorizontalAlignment','left',...
    'Callback',@change_path,...
    'UIContextMenu',hist_cm);
hist_menus = [];
hist_cb = @history_cb;
hist_menus = make_history_cm(hist_cb,hist_cm,hist_menus,history);

uicontrol('Position',[10 425 80 16],...
    'Style','text',...
    'String','File Filter',...
    'HorizontalAlignment','left')
showallfiles = uicontrol('Position',[100 405 100 20],...
    'Style','checkbox',...
    'String','Show All Files',...
    'Value',0,...
    'HorizontalAlignment','left',...
    'Callback',@togglefilter);
filter_ed = uicontrol('Position',[10 405 80 20],...
    'Style','edit',...
    'BackgroundColor','w',...
    'String',filter,...
    'HorizontalAlignment','left',...
    'Callback',@setfilspec);
viewfullpath = uicontrol('Style','checkbox',...
    'Position',[380 335 230 20],...
    'String','Show full paths',...
    'Value',show_full_path,...
    'HorizontalAlignment','left',...
    'Callback',@showfullpath);
remove_dupes = uicontrol('Style','checkbox',...
    'Position',[380 360 230 20],...
    'String','Remove duplicates (as per full path)',...
    'Value',nodupes,...
    'HorizontalAlignment','left',...
    'Callback',@removedupes);
uicontrol('Position',[380 405 350 20],...
    'Style','text',...
    'String','Selected Files',...
    'HorizontalAlignment','center')
uicontrol('Position',[280 80 80 30],'String','Done',...
    'Callback',@done);
uicontrol('Position',[280 30 80 30],'String','Cancel',...
    'Callback',@cancel);

if ~isempty(prop.numfiles)
    uicontrol('Position',[380 385 350 16],...
        'Style','text',...
        'String',numstr,...
        'ForegroundColor','r',...
        'HorizontalAlignment','center')
end

set(fig,'HandleVisibility','off')

uiwait(fig)

% Compute desired output.
switch prop.output
    case 'cell'
        out = full_file_picks;
    case 'struct'
        out = dir_picks(:);
    case 'char'
        out = char(full_file_picks);
    case 'cancel'
        out = 0;
end

% -------------------- Callback functions --------------------

    function add(varargin)
        values = get(navlist,'Value');
        for i = 1:length(values)
            dir_pick = fdir(values(i));
            pick = dir_pick.name;
            pick_full = fullfile(current_dir,pick);
            dir_pick.name = pick_full;
            if ~nodupes || ~any(strcmp(full_file_picks,pick_full))
                file_picks{end + 1} = pick;
                full_file_picks{end + 1} = pick_full;
                dir_picks(end + 1) = dir_pick;
            end
        end
        if show_full_path
            set(pickslist,'String',full_file_picks,'Value',[]);
        else
            set(pickslist,'String',file_picks,'Value',[]);
        end
        set([removebut,moveupbut,movedownbut],'Enable','off');
    end

    function remove(varargin)
        values = get(pickslist,'Value');
        file_picks(values) = [];
        full_file_picks(values) = [];
        dir_picks(values) = [];
        top = get(pickslist,'ListboxTop');
        num_above_top = sum(values < top);
        top = top - num_above_top;
        num_picks = length(file_picks);
        new_value = min(min(values) - num_above_top,num_picks);
        if num_picks == 0
            new_value = [];
            set([removebut,moveupbut,movedownbut],'Enable','off')
        end
        if show_full_path
            set(pickslist,'String',full_file_picks,'Value',new_value,...
                'ListboxTop',top)
        else
            set(pickslist,'String',file_picks,'Value',new_value,...
                'ListboxTop',top)
        end
    end

    function open(varargin)
        values = get(navlist,'Value');
        if fdir(values).isdir
            if strcmp(fdir(values).name,'.')
                return
            elseif strcmp(fdir(values).name,'..')
                set(dir_popup,'Value',min(2,length(path_cell)))
                dirpopup();
                return
            end
            current_dir = fullfile(current_dir,fdir(values).name);
            history{end+1} = current_dir;
            history = unique(history);
            hist_menus = make_history_cm(hist_cb,hist_cm,hist_menus,...
                history);
            full_filter = fullfile(current_dir,filter);
            path_cell = path2cell(current_dir);
            fdir = filtered_dir(full_filter);
            filenames = {fdir.name}';
            filenames = annotate_file_names(filenames,fdir);
            set(dir_popup,'String',path_cell(end:-1:1),'Value',1)
            set(pathbox,'String',current_dir)
            set(navlist,'ListboxTop',1,'Value',[],'String',filenames)
            set(addbut,'Enable','off')
            set(openbut,'Enable','off')
        end
    end

    function clicknav(varargin)
        value = get(navlist,'Value');
        nval = length(value);
        dbl_click_fcn = @add;
        switch nval
            case 0
                set([addbut,openbut],'Enable','off')
            case 1
                set(addbut,'Enable','on');
                if fdir(value).isdir
                    set(openbut,'Enable','on')
                    dbl_click_fcn = @open;
                else
                    set(openbut,'Enable','off')
                end
            otherwise
                set(addbut,'Enable','on')
                set(openbut,'Enable','off')
        end
        if strcmp(get(fig,'SelectionType'),'open')
            dbl_click_fcn();
        end
    end

    function clickpicks(varargin)
        value = get(pickslist,'Value');
        if isempty(value)
            set([removebut,moveupbut,movedownbut],'Enable','off')
        else
            set(removebut,'Enable','on')
            if min(value) == 1
                set(moveupbut,'Enable','off')
            else
                set(moveupbut,'Enable','on')
            end
            if max(value) == length(file_picks)
                set(movedownbut,'Enable','off')
            else
                set(movedownbut,'Enable','on')
            end
        end
        if strcmp(get(fig,'SelectionType'),'open')
            remove();
        end
    end

    function dirpopup(varargin)
        value = get(dir_popup,'Value');
        len = length(path_cell);
        path_cell = path_cell(1:end-value+1);
        if ispc && value == len
            current_dir = '';
            full_filter = filter;
            fdir = struct('name',getdrives,'date',datestr(now),...
                'bytes',0,'isdir',1);
        else
            current_dir = cell2path(path_cell);
            history{end+1} = current_dir;
            history = unique(history);
            hist_menus = make_history_cm(hist_cb,hist_cm,hist_menus,...
                history);
            full_filter = fullfile(current_dir,filter);
            fdir = filtered_dir(full_filter);
        end
        filenames = {fdir.name}';
        filenames = annotate_file_names(filenames,fdir);
        set(dir_popup,'String',path_cell(end:-1:1),'Value',1)
        set(pathbox,'String',current_dir)
        set(navlist,'String',filenames,'Value',[])
        set(addbut,'Enable','off')
    end

    function change_path(varargin)
        proposed_path = get(pathbox,'String');
        % Process any directories named '..'.
        proposed_path_cell = path2cell(proposed_path);
        ddots = strcmp(proposed_path_cell,'..');
        ddots(find(ddots) - 1) = true;
        proposed_path_cell(ddots) = [];
        proposed_path = cell2path(proposed_path_cell);
        % Check for existance of directory.
        if ~exist(proposed_path,'dir')
            uiwait(errordlg(['Directory "',proposed_path,...
                '" does not exist.'],'','modal'))
            return
        end
        current_dir = proposed_path;
        history{end+1} = current_dir;
        history = unique(history);
        hist_menus = make_history_cm(hist_cb,hist_cm,hist_menus,history);
        full_filter = fullfile(current_dir,filter);
        path_cell = path2cell(current_dir);
        fdir = filtered_dir(full_filter);
        filenames = {fdir.name}';
        filenames = annotate_file_names(filenames,fdir);
        set(dir_popup,'String',path_cell(end:-1:1),'Value',1)
        set(pathbox,'String',current_dir)
        set(navlist,'String',filenames,'Value',[])
        set(addbut,'Enable','off')
        set(openbut,'Enable','off')
    end

    function showfullpath(varargin)
        show_full_path = get(viewfullpath,'Value');
        if show_full_path
            set(pickslist,'String',full_file_picks)
        else
            set(pickslist,'String',file_picks)
        end
    end

    function removedupes(varargin)
        nodupes = get(remove_dupes,'Value');
        if nodupes
            num_picks = length(full_file_picks);
            [unused,rev_order] = unique(full_file_picks(end:-1:1));
            order = sort(num_picks + 1 - rev_order);
            full_file_picks = full_file_picks(order);
            file_picks = file_picks(order);
            if show_full_path
                set(pickslist,'String',full_file_picks,'Value',[])
            else
                set(pickslist,'String',file_picks,'Value',[])
            end
            set([removebut,moveupbut,movedownbut],'Enable','off')
        end
    end

    function moveup(varargin)
        value = get(pickslist,'Value');
        set(removebut,'Enable','on')
        n = length(file_picks);
        omega = 1:n;
        index = zeros(1,n);
        index(value - 1) = omega(value);
        index(setdiff(omega,value - 1)) = omega(setdiff(omega,value));
        file_picks = file_picks(index);
        full_file_picks = full_file_picks(index);
        value = value - 1;
        if show_full_path
            set(pickslist,'String',full_file_picks,'Value',value)
        else
            set(pickslist,'String',file_picks,'Value',value)
        end
        if min(value) == 1
            set(moveupbut,'Enable','off')
        end
        set(movedownbut,'Enable','on')
    end

    function movedown(varargin)
        value = get(pickslist,'Value');
        set(removebut,'Enable','on')
        n = length(file_picks);
        omega = 1:n;
        index = zeros(1,n);
        index(value + 1) = omega(value);
        index(setdiff(omega,value + 1)) = omega(setdiff(omega,value));
        file_picks = file_picks(index);
        full_file_picks = full_file_picks(index);
        value = value + 1;
        if show_full_path
            set(pickslist,'String',full_file_picks,'Value',value)
        else
            set(pickslist,'String',file_picks,'Value',value)
        end
        if max(value) == n
            set(movedownbut,'Enable','off')
        end
        set(moveupbut,'Enable','on')
    end

    function togglefilter(varargin)
        value = get(showallfiles,'Value');
        if value
            filter = '*';
            set(filter_ed,'Enable','off')
        else
            filter = get(filter_ed,'String');
            set(filter_ed,'Enable','on')
        end
        full_filter = fullfile(current_dir,filter);
        fdir = filtered_dir(full_filter);
        filenames = {fdir.name}';
        filenames = annotate_file_names(filenames,fdir);
        set(navlist,'String',filenames,'Value',[])
        set(addbut,'Enable','off')
    end

    function setfilspec(varargin)
        filter = get(filter_ed,'String');
        if isempty(filter)
            filter = '*';
            set(filter_ed,'String',filter)
        end
        % Process file spec if a subdirectory was included.
        [p,f,e] = fileparts(filter);
        if ~isempty(p)
            newpath = fullfile(current_dir,p,'');
            set(pathbox,'String',newpath)
            filter = [f,e];
            if isempty(filter)
                filter = '*';
            end
            set(filter_ed,'String',filter)
            change_path();
        end
        full_filter = fullfile(current_dir,filter);
        fdir = filtered_dir(full_filter);
        filenames = {fdir.name}';
        filenames = annotate_file_names(filenames,fdir);
        set(navlist,'String',filenames,'Value',[])
        set(addbut,'Enable','off')
    end

    function setrefilter(varargin)
        fdir = filtered_dir(full_filter);
        filenames = {fdir.name}';
        filenames = annotate_file_names(filenames,fdir);
        set(navlist,'String',filenames,'Value',[])
        set(addbut,'Enable','off')
    end

    function done(varargin)
        % Optional shortcut: click on a file and press 'Done'.
        % 		if isempty(full_file_picks) && strcmp(get(addbut,'Enable'),'on')
        % 			add();
        % 		end
        numfiles = length(full_file_picks);
        if ~isempty(prop.numfiles)
            if numfiles < prop.numfiles(1)
                msg = {'Too few files selected.',numstr};
                uiwait(errordlg(msg,'','modal'))
                return
            elseif numfiles > prop.numfiles(end)
                msg = {'Too many files selected.',numstr};
                uiwait(errordlg(msg,'','modal'))
                return
            end
        end
        delete(fig)
    end

    function cancel(varargin)
        prop.output = 'cancel';
        delete(fig)
    end

    function history_cb(varargin)
        current_dir = history{varargin{3}};
        full_filter = fullfile(current_dir,filter);
        path_cell = path2cell(current_dir);
        fdir = filtered_dir(full_filter);
        filenames = {fdir.name}';
        filenames = annotate_file_names(filenames,fdir);
        set(dir_popup,'String',path_cell(end:-1:1),'Value',1)
        set(pathbox,'String',current_dir)
        set(navlist,'ListboxTop',1,'Value',[],'String',filenames)
        set(addbut,'Enable','off')
        set(openbut,'Enable','off')
    end
end


% -------------------- Subfunctions --------------------

function c = path2cell(p)
% Turns a path string into a cell array of path elements.
c = strread(p,'%s','delimiter','\\/');
if ispc
    c = [{'My Computer'};c];
else
    c = [{filesep};c(2:end)];
end
end


function p = cell2path(c)
% Turns a cell array of path elements into a path string.
if ispc
    p = fullfile(c{2:end},'');
else
    p = fullfile(c{:},'');
end
end


function d = filtered_dir(full_filter)
% Like dir, but applies filters and sorting.
p = fileparts(full_filter);
if isempty(p) && full_filter(1) == '/'
    p = '/';
end
if exist(full_filter,'dir')
    c = cell(0,1);
    dfiles = struct('name',c,'date',c,'bytes',c,'isdir',c);
else
    dfiles = dir(full_filter);
end
if ~isempty(dfiles)
    dfiles([dfiles.isdir]) = [];
end
ddir = dir(p);
ddir = ddir([ddir.isdir]);
% Set navigator style:
%	1 => mix file and directory names
%	2 => means list all files before all directories
%	3 => means list all directories before all files
%	4 => same as 2 except put . and .. directories first
if isunix
    style = 4;
else
    style = 4;
end
switch style
    case 1
        d = [dfiles;ddir];
        [unused,index] = sort({d.name});
        d = d(index);
    case 2
        [unused,index1] = sort({dfiles.name});
        [unused,index2] = sort({ddir.name});
        d = [dfiles(index1);ddir(index2)];
    case 3
        [unused,index1] = sort({dfiles.name});
        [unused,index2] = sort({ddir.name});
        d = [ddir(index2);dfiles(index1)];
    case 4
        [unused,index1] = sort({dfiles.name});
        dot1 = find(strcmp({ddir.name},'.'));
        dot2 = find(strcmp({ddir.name},'..'));
        ddot1 = ddir(dot1);
        ddot2 = ddir(dot2);
        ddir([dot1,dot2]) = [];
        [unused,index2] = sort({ddir.name});
        d = [ddot1;ddot2;dfiles(index1);ddir(index2)];
end
end


function drives = getdrives
% Returns a cell array of drive names on Windows.
letters = char('A':'Z');
num_letters = length(letters);
drives = cell(1,num_letters);
for i = 1:num_letters
    if exist([letters(i),':\'],'dir');
        drives{i} = [letters(i),':'];
    end
end
drives(cellfun('isempty',drives)) = [];
end


function filenames = annotate_file_names(filenames,dir_listing)
% Adds a trailing filesep character to directory names.
fs = filesep;
for i = 1:length(filenames)
    if dir_listing(i).isdir
        filenames{i} = [filenames{i},fs];
    end
end
end


function hist_menus = make_history_cm(cb,hist_cm,hist_menus,history)
% Make context menu for history.
if ~isempty(hist_menus)
    delete(hist_menus)
end
num_hist = length(history);
hist_menus = zeros(1,num_hist);
for i = 1:num_hist
    hist_menus(i) = uimenu(hist_cm,'Label',history{i},...
        'Callback',{cb,i});
end
end
